This invention relates to enrichment of the air/fuel mixture of an internal combustion engine and more particularly to enrichment with oxygen and hydrogen gases produced in a wet plate storage battery which forms a part of the electrical system of the internal combustion engine.
Typically, the electrical systems employed with an internal combustion engine, for example of the type employed in automobiles, includes a generator or alternator, a voltage regulator, a rechargeable or storage battery of the lead-acid type, an ignition switch, an ignition coil, a distributor, and a plurality of spark plugs. During engine operation, electricity generated by the generator or alternator is directed to the rechargeable battery to maintain the battery charge so as to meet the variable loads imposed on the battery during use.
The typical lead/acid storage battery includes a plurality of cells connected in series with each cell producing approximately 2 volts. Each electrical generating cell includes a negative plate group and a positive plate group. Each plate is formed by a lattice-like grid of an alloy of lead and antimony and the grids are filled with a special lead-oxide paste. The amount of current produced by the storage battery is determined by the active area and weight of the materials in the plates and also by the quantity of electrolyte which is typically a dilute sulfuric acid solution. The positive plate material is essentially lead peroxide and the active material of the negative plate is spongy lead. The electrolyte is a solution of sulfuric acid and water. When an electrical load is placed across the positive and negative terminals of the battery, oxygen in the lead peroxide combines with the hydrogen from the sulfuric acid to form water. At the same time, the lead in the lead peroxide combines with the sulfate of the acid to form lead sulfate. At the negative plate, the lead combines with the sulfate of the sulfuric acid to form lead sulfate. The battery is recharged by directing a charging current through the battery in the reverse direction of the discharging current. During charge, the water in the electrolyte is broken down into hydrogen and oxygen through electrolysis. The oxygen collects at the positive plate and the hydrogen collects at the negative plate. The collection of the gas layer at each plate increases the internal resistance of the cell and therefore an increase in charging voltage is necessary to maintain the same charging current flow.
Heretofore, it has been proposed to employ the hydrogen and oxygen produced during battery recharge to supplement and/or enrich the air/fuel mixture employed in the internal combustion engine. An example of one such system may be found in U.S. Pat. No. 1,876,879 to Drabold, entitled CHARGE FORMING APPARATUS FOR INTERNAL COMBUSTION ENGINES, and issued on September 13, 1932. As shown therein, hydrogen produced in the main storage battery of the vehicle ignition and electrical system is collected by a plurality of tubes opening into the space above the electrolyte. The gases are directed via a vacuum line to the throat of a conventional venturi-type carburetor. The Drabold arrangement collects only the gas which is present above the electrolyte during charging of the main storage battery.
A similar system is disclosed in U.S. Pat. No. 3,311,097 to Mittelstaedt, entitled HYDROGEN-OXYGEN DEVICE IN COMBUSTION ENGINES, and issued on Mar. 28, 1967. The storage battery disclosed therein for producing oxygen and hydrogen gases for air/fuel mixture enrichment is provided with an air intake opening. When a vacuum is applied to the space above the cells of the battery, ambient air is drawn in through the intake opening and across the space above the cells. This feature apparently increases the amount of gases which pass to the venturi of a conventional carburetor. Further, it appears that this flow of ambient air assists in cooling the battery during engine operation.
With all of the systems of the type exemplified by the above discussed patents, certain problems are present. For example, during the recharging process in the normal storage battery polarization increases the resistance of the battery and therefore requires an increase in the charging voltage to maintain the charging current flow. Further, during the discharge process, water is formed adjacent the positive plates. In cold weather, this results in an increased tendency for freezing at the positive plates. The need therefore exists, for a hydrogen-oxygen generator capable for use as a primary storage battery in a vehicle electrical system which produces a fairly large amount of gases for enrichment without an increase in internal resistance caused by polarization and further maintains sufficient mixing of the electrolyte to prevent freezing adjacent the positive plates in cold weather.